CALIFORNIA INSTITUTE OF TECHNOLOGY

PASADENA

May 4, 1937

Dear Professor Pauling:

This letter will constitute official notice that at a meeting of the Executive Council of the Institute, held May 3. 1937, you were appointed Chairman of the Division of Chemistry and Chemical Engineering and Director of the Chemical Laboratories.

Very sincerely yours,

Edward C. Barrett

Secretary

Professor Linus G. Pauling

California Institute

May 4, 1937

Dr. Robert B. Corey

Rockefeller Institute for Medical Research

66th street and York Avenue

New York, New York

Dear Dr. Corey:

I would be very glad indeed to have you spend the year in Pasadena under the conditions mentioned in your letter. The Institute would give you an appointment as Research Fellow, without stipend, and would permit the free use of the apparatus and other facilities of our laboratory. On the other hand, I feel that it is my duty to tell you that so far as I can tell, there would be no possibility for you to be added to the staff at the end of the year.

We have available here apparatus for the preparation of Laue photographs and oscillation and rotation photographs, and a large spectrometer constructed by Dr. Sturdivant which has not yet been put in operation. Apparatus which we do not have and which you might well need for your work would include a Weissenberg camera, a simple spectrometer for the rapid measurement of intensities, special apparatus for taking powder photographs, etc. I would recommend that you bring with you apparatus of this type which you think is needed for your own work.

I shall be at Cornell from the end of September to the first of February. During this period Dr. J. H. Sturdivant will be in charge of the crystal structure laboratory and will present for the graduate students a course in crystal structure analysis. If you do decide to spend the year here, it might be good for you to plan to arrive before the 20th of September, in order that you may get settled in the laboratory before I leave for the East.

With best regards, I am

Sincerely yours,

Linus Pauling

LP:mrl

The Rockefeller Institute

For Medical Research

66^th Street and York Avenue

New York

May 8, 1937

Professor Linus Pauling

Gates Chemical Laboratory

California Institute of Technology

Pasadena, California

Dear Professor Pauling:

I was very happy indeed to receive your kind letter granting me the privilege of working in your laboratory next year. I am sending a copy to Dr. Gasser so that the Rockefeller Institute may carry out whatever arrangements are necessary here.

I appreciate your suggestions concerning the apparatus which I might bring with me. As soon as I have opportunity to talk the matter over with Dr. Wyckoff and Dr. Gasser I shall be able to let you know just what this may comprise.

I am looking forward to a very pleasant and profitable year in Pasadena and shall certainly arrive in ample time to get established before you leave for Ithaca.

Very Sincerely Yours,

Robert b. Corey

Near Salinas, about

4 PM

Dearest Ava Helen:

James + Linda saw me off safely, and I've been bowling along ever since. I've written about half of my speech - aside from that I've done nothing but look out of the window. The country is beautiful. We traveled for 130 miles along the ocean, by surf where we camped and on along that fine stretch of coast. The flowers have been wonderful - yuccas in the San Fernando valley, monkey flowers in the Siniu valley near Santa Susanna, and then great fields of mustard and lupin. We passed by the place in Siniu where we all stopped under a tree for lunch.

There was a high wind blowing on the ocean, making whitecaps and forming long Pennous of spray from the tops of breakers.

We got in San Francisco at 6 ⁰⁰ + I leave on the ferry at 6 ⁴⁰ . I think I shall eat dinner on this train at 5- I bought only some dates for lunch, not feeling very hungry.

I love you and miss you very much and I hope you are lonesome for your

Paddy

XXXXX XXXXXX XXXXXXXX XXXXXXXXX

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Kisses forKisses forKisses for Kisses for

Mamma Liney Peter Linda

Noon Tuesday

Near Eugene

[05/11/1937]

Dearest little sweet wife:

I love you very much, and all of our darling little children, too, and I shall be glad to be back with you again Friday morning.

The ride through the Cascades this morning was wonderful - the immense mountains clad both with trees and snow, with occasional clouds or fog both above and below us, and with small bright green trees beneath the great giant deep green conifers. I think I saw two kinds of dogwood - one in the mountains, with small sort of greenish blossoms and very dark green leaves and the other, lower down, with large white blossoms and light green leaves. Also I saw skunk cabbages and many yellow flowers that I can't identify.

I have only talked with one person - a man on the train to San Francisco asked my advice about hotels. His name is Hocking; he has a son who is assistant Professor of French at Northwestern. He lives near Chicago. He said that he and his wife had waited too long - they went to Florida last year together, but then she died before this year's trip to California, and that he hasn't enjoyed coming alone very much.

I have nearly finished writing my address, and I shall be in Albany in a few minutes now.

Your own

Linus.

OO 000 ooo ....

OOO 00000 oooo ......

OO 000 ooo ...

Love to Mamma Love to Linus Love to Peter Love to Linda

HEMOGLOBIN AND MAGNETISM

By Linus Pauling

Talk after banquet for installation of Sigma Xi, Corvallis, Oregon, Wednesday, May 12, 1937.

I am indeed happy to be here on this great occasion. When Professor Graf wrote me that Professors Milne and Simmons and their committee asked me to come, I was strongly tempted to accept, even though my better self told me that I should refuse. I don't mind lecturing to students or at scientific meeting, but a banquet is something different; talks at banquets should be left to the easy talkers - historians, lawyers, economists, philosophers. In this case, however, the tempter won - I decided that I would have the pleasure of coming here even though the audience had to suffer for it.

the general subject that I shall talk about, under the disguise of the title "Hemoglobin and Magnetism", is a new branch of chemistry, modern structural chemistry. this subject involves the determination of the structures of molecules - the exact location of the atoms in space relative to one another - and the interpretation of the chemical and physical properties of substances in terms of the structure of their molecules. the new information about the structure of the molecules is detailed and accurate and goes far beyond the classical structural formulas of the organic chemist in the same way that the final architectural drawings of a building go beyond a preliminary rough sketch. Modern structural chemistry is a new subject - twenty years ago detailed structural information was available for only a half-dozen molecules, and ten years ago for only a few dozen.

Now scores of new molecules are being studied every year, mainly by the physical methods of spectroscopy, x-ray and electron diffraction, measurement of magnetic properties, etc., and the results obtained have been found to be useful for the biochemist studying vitamins as well as for the inorganic chemist studying the complex inorganic substances.

As a single substance to use as an example of the application of the methods of modern structural chemistry I have selected hemoglobin, with particular emphasis on it magnetic properties.

Hemoglobin is the respiratory pigment, carrying oxygen from the lungs to the tissues, for all vertebrates and for many other animals. There is a lot of it around: about 7% of the body weight of a man is blood and about 1/7th of the blood is hemoglobin, so that hemoglobin comprises about 1% of body weight thus amounting to about a pound and a half per person. Hemoglobin is a good chemical substance - it can be obtained in pure crystalline form, put in a bottle, and labeled. Nevertheless, chemists tend to look at it askance, because it is such a complicated substance. It has a molecular weight of about 68,000, the molecule containing about 10,000 atoms. this means that the molecule is very big. It is about 50 Å in diameter, with an Angstrom equal to 1/100 millionth of a centimeter; that is, only five of these molecules in a row would give one millionth of an inch, and a blob containing only about one million of them would be big enough to be seen in the microscope. Hemoglobin consists of a big protein molecule called globin to which there are plastered four small groups, each of about 75 atoms, called hemes. These hemes, each of which consists of one iron atom and a porphyrin group, give hemoglobin its characteristic properties, the globin seems to be useful mainly to keep the substance in solution in the plasma. It is probably used for this purpose because the body is so full of proteins that they are called upon whenever something is needed for a special use. Each of the hemes is able to combine with one oxygen molecule; in this way each hemoglobin molecule can carry four oxygen molecules from the lungs to the tissues. hemoglobin also aids in bringing carbon dioxide from the tissues to the lungs, but it does not do this directly, as I naively supposed until I learned better. hemoglobin instead function in the main indirectly, in the following way. Oxyhemoglobin is a stronger acid than hemoglobin itself. On loosing oxygen in the tissues hemoglobin thus makes the blood plasma basic, permitting it to pick up carbon dioxide as bicarbonate ion; then in the lungs on picking up oxygen the hemoglobin makes the plasma acid, thus expelling the carbon dioxide.

I mentioned that each hemoglobin molecule contains four atoms of iron, there being thus about 3 grams of ron in the blood of the body. It is probably an accident that we eat raising and drink tonic for iron, instead of eating and drinking for copper or manganese or some other metal; for there are other respiratory pigments used by invertebrates which involve these metals in place of iron. Hemocyanin, the blood of crabs, snails, abalone, octopi, etc. Which is blue when oxygenated, colorless when deoxygenated, is a very complex substance, with a molecular weight which may go as high as five million. Hemocyanin contains copper. One of the puzzling facts about it is that it adds one molecule of oxygen for every two atoms of copper. In the old days, when for a reason that was never told to me cuprous chloride was written Cu₂Cl₂, the copper atoms being supposed to occur in pairs in cuprous compounds, this might have been understandable; but now that we know that these pairs don't occur the fact is one to be explained in the future.

It is known that iron-containing substances somewhat like hemoglobin occur in all cells, both plant nd animal. It is possible, although it has not been prove, that a copper compound related to hemocyanin is similarly widespread. If so, this would account for a number of facts. For example, there is evidence that copper is necessary for life in vertebrates, and that it is connected in some way with the formation of hemoglobin in the body. it may be that the prototypes of hemoglobin and hemocyanin are present in all living cells, and that the choice of one or the other as the starting point for developing a respiratory pigment has _____ on an accident. this would account for the widespread occurrence of these pigments nd for the apparent lock of reason in the choice between them - thus all species of snails but one use hemocyanin as respiratory pigment, this one using hemoglobin.

Besides the blue copper blood there exists a green blood (in a worm), called chlorocruorin. This also contains iron, but the pigment is somewhat different from hemoglobin. A manganese blood has been reported for a certain shellfish. Most striking of all, however, is the blood of strange animals cal ascidians, or sea-squirts. These are little animals about 3 inches long which live in sea water, henaging under floats and in similar places. When taken out of water they squirt out a little stream of water, this action having given to their name. Their blood contains corpuscles of different kinds and colors, blue, green, and red, looking in shape something like raspberries. The metal in this blood is vanadium - though how the animal picked this out of the periodic table I can't explain. The process by which the animal gets the vanadium out of the sea water is also puzzling.

Hemoglobin containing four hemes, about which a great deal is known; heme has even been synthesized. heme is a relatively simple substance, the iron salt of a reddish-brown substance called porphyrin, H₄C₃₄H₃₀N₄O₄. Heme itself, separate from globin, can be found in nature in at least one place - as crystals in the blood of the old males of the marine worm urechis. The porphyrin obtained by removing the iron atom is more widely distributed; the brown color of brown eggs is due to a prophyrin, called Ooporphyrin - it is the same as that in blood. Also, the brown stripe down the middle of the back of an angleworm is due to porphyrin. The blue pigment, called turacin, in the feathers of the South African bird Turaco is the copper salt of a porphyrin.

And with this parting word for the president of the new chapter, and with the best wishes and great hopes for the chapter itself, I come to the end.

May 19, 1937

Dr. W. G. Penney

Department of Mathematics

Royal College of Science

Imperial College of Science and Technology

South Kensington, London S.W.7., England

I omitted to mention in my letter that we had determined the carbon-carbon single bond distance in ethane and in many other hydrocarbons. In every case the [v]alue found is 1.54 Å to within the experimental error, about 0.02 Å. In ethane itself our value is 1.55 Å, the carbon-hydrogen distance being 1.09 ± 0.03 Å.

Sincerely yours,

Linus Pauling

LP:mrl

The Rockefeller Foundation

May 19, 1937

Dear Linus:

As I suggested in my note of April 22, there are a variety of points relative to the application, which is now before this division, from the CIT, which can, I think, profit by somewhat more extended and detailed consideration.

1) First of all, as I reported orally to Dr. Millikan when he was recently here, it will not be possible to obtain a decision on this request before December of this year. Any modification or amplification of the present request should therefore take this fact into account, indicating the beginning date at which the support is requested to commence.

2) I think that it is somewhat more detailed and somewhat more con-sidered description of the project than was feasible for you to prepare in the time which was available when the application of March 27 was sent in. Among other points which could perhaps profit by some amplification and some further consideration, I would mention the fact that we would wish to have a reasonably definite indication of the cost of the initial equipment for the organic laboratories. On account of a certain prejudice, perhaps illogical but still understandable, which exists here relative to the purchase of books and journals, it would also help me if I had some indication of the expenditures of this sort which you feel it is essential to make.

3) The total request which is before us includes the sum of $50,000 a year for organic and structural chemistry and also includes $25,000 a year in support of certain work in biology. The latter portion of the request was given, I think you must agree, rather casual treatment. Aside from the relatively brief reference to this request in Dr. Millikan's formal letter of application, there was no supporting description from the Division of Biology.

I entirely realize that the whole request was prepared somewhat hastily, but there are naturally a good many important questions which it would be necessary to discuss before we could give effective consideration to a request of this magnitude.

4) With particular reference to the request for aid in biology, but also with reference to the request that our new grant expand our support of your own work in structural chemistry from $10,000 yearly to $15,000 yearly, I think it is necessary to point out that it is the characteristic business of The Rockefeller Foundation to assist in the initiation of enterprises whech then are able to command appropriate local support. My letter of December 19, 1933 to Dr. Millikan pointed out that The Rockefeller Foundation was extending temporary aid for the development of re-search in biology at the CIT with the understanding "that support for the work in biology is undoubtedly to be forthcoming from normal sources, once the general situation improves." Later in the letter occurs the sentence: "That is, it is our understanding that, if it prove possible to continue this support as described above for the three-year period. The Institute accepts full responsibility from then on," The closing paragraphs of this letter also emphasized the fact that The Rockefeller Foundation could not accept any responsibility for the continuance, beyond the three-year period then under consideration, of the support of your own researches. I do not refer back to these old understandings in any present spirit of low bargaining. It is, however, necessary to emphasize that The Rockefeller Foundation would consider it a somewhat retrograde step, from our point of view, to expand assistance of your own work by $5,000 annually, now absorbing into our support a portion, the furnishing of which from local sources was one of the strong motivations of our original grant. For similar reasons, there would be a heavy burden of proof against now expending so large a sum for the support of the work in biology - a sum nearly as large as that which was previously granted on a basis which was explicitly emergency and non-recurring. I quite realize that the Institute has not found it possible, during the last two or three years, to increase its resources as effectively as had been hoped; and I believe that there would be a reasonably sympathetic attitude here in connection with a proposal which involved our continuing some more modest portion of this past support.

5) In view of all of the foregoing remarks I have been wondering if it would be possible for your colleagues and yourself to work out a desirable and acceptable plan on the basis of approximately $60,000 annyally for 5 years. In my own mind I find myself tentatively supposing that approximately $10,000 of this sum would be devoted to work in biology, perhaps to those aspects which are most closely and naturally connected with the proposed development io bio-organic chemistry. I have also tentatively supposed that the allocation, from the remaining sum of $50,000 yearly, for your own work in structural chemistry could be kept at its previous figure of $10,000, the Institute continuing to accept responsibility for contribution $5,000 for this project from other sources. If such an arrangement is feasible, the remaining sum of $40,000 annually would provide for the pro-posed $35,000 annual budget for organic chemistry and still leave an annual sum of $5,000 (or a total of $25,000 for the five-year period) which could be used primarily for permanent equipment. The major portion of this permanent equipment would presumably be required during the first year: but it seems doubtful and indeed undesirable that the program in organ organic chemistry should be at once brought to the $35,000 level. Do you not think that it would be sensible to open up the program rather slowly? If this were done, it would probably be possible to arrange a decreasing schedule for equipment and an increasing schedule for salaries, stipends, etc., so that the annual total would be approximately constant. It would not, of course, becnecessary to handicap the develop-ment of the program just because of an artificial demand that the annual expenditures be equal. Thus it would be possible to give consideration to an appropriation which would provide a total of $300,000 over five years with the understanding that not more than, say, $70,000 be spent in any one particular year, thus allowing some degree of elasticity in the annual sums. It has further occurred to me that it might even be desirable for you to give consideration to the possibility of entering still more slowly upon the proposed program, and considering a proposed total of $300,000 over a period of six years rather than over a period of five. That, however, is a point on which I have no strong feeling,

6) I am sure that Professor Morgan and you will both realize that the foregoing remarks do not carry with them the slightest implication that we are more interested in the Chemistry Division than we are in the Biology Division. The feeling that we are not justified in now contributing so heavily to the research in biology, but that we are justified in considering the initiating of support for the work in bio-organic chemistry, is based upon precisely the same considerations which might entirely naturally lead us, at some future time, to reverse the role of the two subjects and give preferred consideration to the development of some aspect of the work in biology.

This rather long and somewhat complicated letter may give rise to several questions on your part; and I know that you will feel entirely free to write to me as informally as you please to carry forward the discussion. Inasmuch as this application primarily refers to chemistry, but also includes a discussion of the work in biology, I am sending a copy of this letter to Professor Morgan for his information.

Cordially yours,

Warren

Professor Linus Pauling

Gates Chemical Laboratory

California Institute of Technology

Pasadena, California

May 25, 1937

Dr. A. E. Mirsky

Hospital of the Rockefeller Institute

66th Street and York Avenue

New York, New York

Dear Alfred:

Many thanks for your letter about my new position. I do not know how it is going to work out but so far the change has not been for the worse since I have successfully avoided taking on any duties except a few of the simplest.

Our work in general is progressing at a satisfactory rate. I am sending reprints of the ferrihemoglobin work separately. Coryell is now working on denaturation and the effect of urea and alcohol and similar agents. He finds that concentrated urea in the middle pH range does not denature ferrihemoglobin although it causes a small change in the moment of both the ion and the hydroxide. Stitt has been looking for new compounds. He has evidence for a ferrohemoglobin cyanide and ferrihemoglobin formate as well as some others. He has been given a National Research Fellowship for next year and will leave for Harvard to work with Wilson in August. Coryell will stay here.

Astbury is here on a short visit. He gave a very interesting account of his work in a seminar talk yesterday, and showed some fine photographs of proteins. His ideas regarding muscle contraction, though rather vague, seem to be well founded on experiment.

How is your work progressing? Have you succeeded in building up a staff as you had planned?

What is your opinion of Niemann, who has been given an appointment here as Assistant Professor of Organic Chemistry?

With best regards to Reba and the children as well as to you,

I am

Yours,

Linus Pauling

LP:mrl

May 27, 1937

Dr. Paul Emmett

Fixed Nitrogen Research Laboratory

Washington, D.C.

Dear Paul:

I have heard a word of mouth rumor that you have been made head of the Department of Chemical Engineering and Host Engineering at Johns Hopkins University, and I wish to offer my heartiest congratulations not only to you but also to Hopkins, which could not have got a better man. In case that I haven't heard correctly regarding the nature of the position, I would be glad also to be set right.

I have been intending for many months to write to you about my ungracious behavior while in Washington last year. After I had rented a car and taken Ava Helen off for a ride in Virginia, she began a program designed to convince me that that was the wrong thing for me to have done, and I gradually began to realize that you would not have considered it an imposition to have taken us on this trip. I had been afraid to mention that we would like to do this, for fear that we would impose on you. In case that you felt that I had done the wrong thing, I wish to apologize, and to promise to behave better the next tine. I hope, too, that I never have a week in Washington which allows so little free time for visiting as that week did.

I am working hard now on various researches and on a book on the quantum mechanics of organic molecules, in collaboration with Wheland. Brookway is finishing up a lot of electron diffraction work, in preparation for leaving on his Guggenheim Fellowship for England on August 15th. He will teach physical chemistry at the University of Michigan after returning. Sturdivant is working on a new x-ray apparatus for the study of solutions; I am hoping that it will provide a great number of interesting results.

With best regards to you and to your wife, I am

Sincerely yours,

Linus Pauling

LP:mrl